Welcome to the most active Linux Forum on the web.
Go Back > Forums > Linux Forums > Linux - Software
User Name
Linux - Software This forum is for Software issues.
Having a problem installing a new program? Want to know which application is best for the job? Post your question in this forum.


  Search this Thread
Old 02-14-2009, 11:43 AM   #1
LQ Newbie
Registered: Jul 2005
Posts: 5

Rep: Reputation: 0
usb disk speed problem

i have a strange problem with my usb disk,it is odd enough I think!
the operating system i used is opensuse 11.1 64 bit,I found that
when i copy a file from my pc to my usb disks or usb mobile drivers,the speed is very slow if the file is not big enough,i have try with some files.
if the file is big enough(maybe bigger than 2GB ) the speed is perfect(about 15MB/S).but if the file is not so big(such as 700MB),the transform speed is very slow(about 2~3MB/S).I have try may
files with different file size, using my flash disks and 2.5"mobile drivers.They all have same problem.when i copy a file about 700MB it might cost 5 minutes(compared with speed in vista,it is slower),but if copy a file about 2500MB it also cost about 5 minutes(exactly less than 5 minutes).
does that have some thing to do with my system settings,or else?
puzzled me a lot!

Last edited by wangduanzhu; 02-14-2009 at 11:45 AM.
Old 02-15-2009, 05:04 AM   #2
Senior Member
Registered: Jan 2008
Location: Urbana IL
Distribution: Slackware, Slacko,
Posts: 3,716
Blog Entries: 3

Rep: Reputation: 483Reputation: 483Reputation: 483Reputation: 483Reputation: 483
Your computer MAY have a combination of USB 1.1 & 2.0 Ports. Look in Device Manager. If the device says "enhanced" then it is USB 2.0. Your solution would be to move the external to a different port or install a USB 2.0 PCI card. Also, keep in mind that other devices using that USB controller and other devices using the same IRQ can slow things down more.

The theoretical transfer rate for USB 2.0 is 400Mb, which equals 50MBs. The actual transfer rates will be substantially less, but shouldn't be as low as 3MBs. Are you using a USB hub or ports on a KBoard?
Check to see what IRQ setting is used for the USB and what else, if anything is also sharing that IRQ.
Just looked at my Advanced settings for the USB controllers. There is a screen stating that the controller shares bandwidth and is fixed at 10 percent. This is sharing bandwidth with the PCI bus. Some BIOSes allow disabling of PCI slots to conserve bandwidth. Check your BIOS to see if there is such a setting. If so, disable PCI slots not in use, if possible.
while in bios set to non windows or no OS if so linux just reads bios. like it is supposed to do. Unlike widows that control bios.

as you can see some one wrote a driver for windows that supports faster transfer rates. You will have to read up on the usb devices and DMA

there is different modules for usb storage devices and in a stock kernel it may not be set up or has detected it wrong.

Last edited by Drakeo; 02-15-2009 at 05:06 AM.


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Slackware 12.1: Problem with disk access speed. andrew.46 Slackware 1 05-05-2008 05:52 PM
USB 2.0 speed degraded to USB 1.1 speed friendship7 Debian 5 07-13-2006 01:22 AM
Speed problem with USB storage devices PhobosK Linux - Hardware 1 10-16-2005 07:35 AM
DISK Speed (Transfer LOW) PROBLEM! apinta10 Slackware 8 10-11-2005 03:15 AM
USB Hi-Speed problem in 10.1 tmmort Slackware 2 08-30-2005 04:17 AM > Forums > Linux Forums > Linux - Software

All times are GMT -5. The time now is 03:37 AM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration